Rotary contactor device



Sept. 16, 1952 P. VAN s. KOLFF ROTARY CONTAUIOR DEVICE Fild Oct. 4, 19512 SHEETS-SHEET 1 R O T N E V m ikfwkw ATTOR JEYS Sept- 1952 P. VAN s.KOLFF 2,611,051

ROTARY CONTACTOR DEVICE Filed 001. 4, 1951 2 SHEETS-SHEET 2 INVENTOR9%., M mma ATTORNEYS Patented Sept. 16, 1952 UNITED STATES PATENT OFFICE16 Claims.

The present invention relates to electric switching device and inparticular toan improved construction for switches of the type wherein aplurality oi'contacts are arranged in a contact circle and circuitstherethrough are completed selectively in accordance with the angularposition of a control member which is arranged for rotation about anaxis coincident with the center of the contact circle.

In one well-known construction the rotary control member is comprised ofa contact member which as it rotates engages the stationary contactmembers in succession thus establishing cir cuits through the rotarycontact member and each of the stationary contacts in succession. If therotary contact member rotates continuously one thus obtains periodicswitching in the circuits associated respectively with the several fixedcontacts such as in an ignition timer device for internal combustionengines. If the rotary contact member is associated with an angularpositioning device'such as a wind direction indicating vane then thecircuits established respectively between the rotary contact and thecircular array of fixed contacts can be used to telemeter the vanedirection to a remotely disposed direction indicating instrument.

According to another well-known construction sometimes referred to as adrunken wheel switch the rotary contact member is constituted by awobble plate; which is made to wobble about its axis either by means ofan eccentric linkage mechanism or a camriding in frictional contact withthe wobble plate to the end that the low point on the periphery of thecontact plate travels progressively around a circular path to engage, insuccession, the several fixed contacts which are disposed along thepath.

In still another type of construction, sets of relatively movablecontacts are disposed along a circularpath and a. magnet rotating on anaxis coincident with the center of said path eiiects momentary closureor opening, whichever is desired, oi the contacts sets in succession byits inherent attractive force on the contacts.

In all of the about types of switching devices, however, a considerableamount of torque must be available for turning the rotary contactmembe:- and in the case of the rotary magnet type, the magnet must beworked cyclically between several miniimnn and maximum attraction phasesfor each revolution which effects corresponding but undesirable changesin the loading torque.

A primary object of the present invention is to provide an improvedconstruction for a rotary switch or contactor device which because of anentirely new operating principle involved can be used reliably inapplications where the driving torque is of a very low order such as forexample in a wind direction indicating system where the torque on theweath r vane is, in the case of a feeble wind, often only a fewinch-ounces. Other low-torque systems for which the switching deviceaccording to this invention can be used will be readily suggested tothose familiar with the switching art.

In accordance with this invention the contactor device is characterizedby a contact disc of magnetic material arranged for displacement about acentral axis, a plurality of contactsarranged in spaced relation along acontact circle concentric with the central axis, and a magnet having itspole portions arranged for movement along an arcuate path concentricwith the central axis adjacent a peripheral portion of the disc surfaceand circumferentially thereof. The magnetic attraction of the disc tothe poles of the magnet is both continuous and uniform, and as themagnet poles progress along their circular path, a progressivelychanging portion of the disc periphery is displaced in the direction ofthe poles to cause a corresponding progressively changing portion of thedisc periphery to engage the contacts located on the contact circle insuccession.

In one embodiment of the invention which will be hereinafter described,the magnetic contact disc is mounted on a ball and socket bearing toexecute a wobble motion about the central axis as the magnet is rotated,and the progressively changing low point on the disc periphery travelsprogressively around the contact circle.

In another embodiment also to be described the contact disc is caused toexecute an oscillating motion about the central axis in a planetransverse to that axis as the magnet rotates causing a progressivelychanging peripheral portion of the disc to be displaced radially outwardto engage the contacts on the contact circle in succession.

In the accompanying drawings which illustrate these two embodiments:

Fig. l is a view in vertical section of the embodiment wherein therotating magnet element of the switching or contactor device cooperateswith a contact disc of the Wobbler type, the application of theswitching device being to a wind direction indicator system;

Fig. 2 is a transverse section on line 22 of Fig. 1;

Figs. 3 and 4 are views in side elevation and top plan, respectively ofthe rotary magnet and its support;

Figs. 5 and 6 are views in elevation of the contact disc and thecircular array of fixed contacts associated therewith showing twodifferent positions of contact of the former on the latter;

Fig. 7 is a circuit diagram showing the rotary switching device and itsconnections to the repeater instrument for indicating different angularpositions of the weather vane;

Fig. 8 is a view in vertical section of an embodiment of the inventionwherein the contact disc whose motion is controlled by the rotatingmagnet is arranged for oscillatory displacement in a progressivelychanging radial direction towards the circular array of fixed contactswhich surround the periphery of the disc;

Fig. 9 is a transverse section on line 9-9 of Fig. 8;

Fig. 10 is a plan view of the contact disc;

Fig. 11 is a perspective view of the rotary magnet used in the Fig. 8construction; and

Fig. 12 is a view similar to Fig. 11 illustrating a modified form ofmagnet which can be used in lieu of the construction shown in Fig. 11.

The contactor device shown in Figs. 1-6 for transmitting angularindications is comprised of a vertical shaft I arranged for rotation ina bearing sleeve 2 which is arranged in an upstanding manner upon acasing 3 and secured thereto by one or more screws 4. A wind directionvane of any desired configuration but here illustrated in the form ofanarrow 5 is secured to a fitting 6 having a bore 6a therein adapted toreceive the upper end of shaft I, and a set screw 1 is used to fastenthe fitting 6 to the shaft I to prevent relative rotation therebetween.Thus as the indicator vane 5 turns with a shift in wind direction theshaft I will also be turned through a like angle. While the materialfrom which the parts are made is not critical, the apparatus will beexposed to the weather and hence it is preferable to make shaft I andbearing sleeve 2 of bronze. Also of bronzecan be the shaft 5a of theweather vane and brass can be used for the vane fitting t. Casing 3 canbe of galvanized iron or steel.

The lower end of shaft l extends within casing 3 and has fastenedthereto by set screw 9 an arcuate block In of non-magnetic material suchas brass. Block IE! as shown in Fig. 4 has a fiat Illa along one side towhich is secured by screw II a permanent magnet I2 having verticallydepending poles Ila, I2b which travel along a circular path concentricwith the axis of shaft I.

Situated beneath the rotatable assembly con,- sisting of vane 5, shaftI, block I II and magnet I2 is a circular plate I3 made from anysuitable electrical insulating material having a peripheral rib portionI3a by which it is held in a horizontal position between the edges ofthe upper and lower halves of casing 3. The two casing halves 3a and 3bare held togetherby a plurality of bolts I4 which extend longitudinallythrough the same between the end walls 30.

' Plate I3 is arranged concentric with the axis of shaft I and carries aplurality of stationary contact members I Ea-I 5h arranged in spacedrelation along a contact circle also concentric with the axis of shaftI. In the illustrated embodiment, the upper ends of these stationarycontacts project above the surface of plate I3 for' a reason which willbe later explained, but such contacts could be arranged flush with thedisc vane 5 4 surface for certain other applications of the inventiveprinciple herein disclosed without departing from the spirit and scopeof the invention. Also carried by plate I3 and upstanding upon andconcentric with the center thereof is a socket I6 which receives a ballmember I'i secured to a thin circular disc I8 of magnetic material suchas soft iron. In the illustrated embodiment, disc I8 is provided with acentral aperture of substantially the same diameter as ball I1 and thelatter is soldered to the edge of the aperture along substantially agreat circle on the ball. The lower half of ball I? thus rides in socketI 6 and a portion of the upper half is adapted to contact an arcuaterecess I9a provided in the underface of a block of insulating materialI9 secured to the bottom face of shaft I to prevent any possible"grounding of the electrical circuit. However, it is to be noted that athrust bearing 20 placed between the confronting end faces of bearingsleeve 2 and fitting 6 carries the entire vertical loading of therotatable assembly and hence no pressure whatsoever is placed upon ball.

IT by shaft I. In this manner disc I8 is rendered free from all loadingexcept an inconsequential amount due to the contact pressure between theball and socket members of the bearing for the disc attributable to thecombined mass of disc and ball.

Attached to the underface of disc I8 near its periphery is contact ring22 of copper or other good electrically conductive material. The latteris also concentric with the axis of shaft I and is adapted to engage thestationary contacts .I5a-I5h in succession as shaft I is rotated. Ifdesired, however, it is also possible to omit the contact ring and havethe rimof the disc engage the contact directly.

With reference now to Fig. 1, it will be seen that with the shaft I andmagnet I2 in the angular position depicted, the right side of disc I8,being of magnetic material is tilted upward due to its magneticattraction to the depending poles I2a, I2b. The opposite side of disc I8is of course tilted downwardly to bring that side of contact ring 22into engagement with the stationary contact member I541 on that side, asshown in Fig. 5. Hence as the angular position of shaft I and hence alsomagnet I2 changes, the continuous and uniform attraction between aprogressively changing circumferential portion of disc as and the magnetpoles will cause the low point'cf Contact ring 22 to roll progressivelyalong the circumference of the contact circle and establish contact withthe contacts I5a-I5h in succession.

Disregarding the magnetic forces of attraction between magnet I2 anddisc I8, the latter is staticaliy balanced to as fine a degree as ispossible forall tilt angles and hence practically no work is required ofthe magnet to change from one tilt angle to another as shaft I changesits angular position. Hence a minimum of torque is required to turnshaft I and the wind indicator will thus be responsive to winds of verylow velocities. Also it should be noted that the attractive forcebetween disc I8 and magnet I2 being constant, the torque required torotate shaft I will likewise be constant.

Fig. 7 shows one arrangement for telemetering the angular positions ofweather vane 5 to an instrument located remotely therefrom. The

repeater instrument shown schematically only card with the points of thecompass denoted thereon in any desired manner. In the illustratedembodiment, the card consists of eight major bearing indications spaced45 apart legended respectively N, NE, E, SE, S, SW, W and NW, andelectric lamps 24a-24h are located beneath plate 23 in radial alignmentrespectively with the eight major bearings. Other minor bearingindications are located midway between each pair of the eight majorbearings to indicate the other eight bearings such as NNE between N andNE, NNW between NW and N, etc.

The eight fixed contacts l5af-I5h on plate I3 are likewise spaced 45apart and are electrically connected by conductors 25 to one terminal oftheir correspondingly positioned lamps 24a-24h. The other terminals onthese lamps are all connected together to ring conductor 28, conductor21 leads from conductor 26 to one terminal of a source of powerindicated by battery 28, and conductor 29 extends from the otherterminal on battery 28 to the contact ring 22 via socket l6, ball I! anddisc I8, the latter three elements being also electrically conductive.As shown in Fig. 1, the conductors extending between casing 3 andtheremotely located repeater instrument are carried through conduits 30.

Thus for example assuming that when the wind direction is from thenorth, contact ring 22 will be tilted so as to engage contact I5a andthis will establish a circuit through battery 28 for energizing lamp 24abeneath the N" designation on the compass card. In a similar manner,each of the other seven major wind directions will be made known to theobserver.

Should the wind direction be from a direction midway between two of theeight major compass bearings such as NNW which is between "NW and N,then contact ring 22 will be in the position shown in Fig. 6 wherein itengages both contact I5h and I50. thus energizing two lamps 24h and 24a.With both the N and NW indicia illuminated, this indicates to theobserver that the wind direction is between N and NW. The contact ring22 is of course able to bridge simultaneously two, but not more thantwo, adjacently positioned contacts such as I5h and I5a because thelatter project above the surface of plate I3 and hence make it possiblefor the low point on the ring to dip between them. For otherapplications which require successive but nonoverlapping engagementbetween the disc and contact, the latter could be arranged flush withthe surface of plate I 3 in which case contact ring 22 would engage thecontacts [Ea-[5h one at a time only.

Another construction wherein the magnetic attractive force actscontinuously upon a progressively changing peripheral portion of acontact member is shown in Figs. 8-12 wherein the magnetic disc member,instead of undergoing a wobble motion'about the central bearing axisupon rotation of the magnet as in the embodiment previously explained,is caused to execute an oscillating motion about the central axis in aplane transverse to that axis to bring a progressively changingperipheral portion of the disc into successive engagement with thecontacts.

With reference now to Figs. 8-11, the angular input shaft is designatedby numeral I and in the interest of simplifying the drawings, the vanestructure by which the shaft is rotated has been deleted. The lower partof shaft I containing the contactor mechanism is enclosed by a cupshaped housing 32 preferably of insulating material having a cap 32asecured thereto by screws 33, and bronze bearing sleeves 34, 35 set intothe body of housing 32 and cap 32a provide bearings for the shaft.

Mounted on the cylindrical shaft I and fixed thereto by pins 36 are apair of magnets 31, 38 extending radially of the shaft axis havingunlike poles, i. e., N--S, of arcuate shape arranged in confrontingspaced relation. Disposed butween the magnets and likewise mounted uponand secured to shaft I by pins 39 are a pair of circular guide plates40, 4| of a wear-resistant material such as for example hard bronze.Plates 4!], 4| are arranged in spaced parallel relation concentric withthe axis of shaft I and a disc 42 of iron or other magnetic material isdisposed around the shaft between plates -4I, the disc including aplurality of anti-friction roller means such as balls 43 mounted inapertures in the body thereof adapted to establish a rolling surfacecontact with plates 4!], 4!. Shaft I extends through a central, circularaperture 42a in disc 42 and the diameter of the aperture is made largerthan the diameter of shaft I by an amount at least equal to the radialdisplacement of the disc 42. Preferably the diameter of aperture 42a ismade slightly larger than the radial displacement of disc 4-2 to al lowfor contact wear.

The diameter of disc 42 is made somewhat less than the radial length ofthe magnets 31, 38 so that as illustrated in Fig. 8 the magnetic fieldbetween the pole portions of magnets 31, 33 will draw the disc radiallyto a position eccentric of the shaft axis.

Spaced in a circle surrounding the disc 42 are a plurality of fixedcontact members 44 adapted to be contacted in succession by theprogressively changing portion of the periphery of disc 42 which isdrawn radially outward between the confronting poles of magnets 31, 33.As in the previous embodiment, eight fixed contact members spaced 45apart around a circle concentric with the axis of shaft I are used andthe periphery of disc 42 will engage two adjacently positioned contactmembers when the radius along which the disc 42 is shifted is locatedmidway between adjacent contact members. Leads (not shown) from thefixed contacts 44 and from the rotary shaft I are taken out of thehousing 32 through aperture 322) in the wall thereof. In thisembodiment, the electrical path to disc 42 extends from the shaft Ithrough guide plates 40, 4| and balls 43, the surfaces of which are inconstant contact with disc 42.

Fig. 12 illustrates an alternative form of magnet component which can besubstituted in the Fig. 8 assembly for the one shown in Fig. 11. In theFig. 8 construction, two magnets as shown in Fig. 11 are required andthe flux gap between the confronting faces of the unlike poles of themagnets extends perpendicular to the plane of disc 42. In thealternative construction shown in Fig. 12, only one magnet 45 isrequired and the N and S poles thereof are so arranged that the flux gapbetween the poles extends circumferentially of the disc 42.

If it be assumed that the contactor device of Fig. 8 is operated in theupright position as illustrated, a magnet construction as shown in Fig.12 could be substituted for the lower magnet 38, thus enablingthe uppermagnet 31 and upper guide plate 40 to be eliminated.

In conclusion I desire it to be understood that the embodiments of myinvention which have herein been illustrated and described are to beconsidered typical rather than limitative of the inventive concept towhich the appended claims are directed, and hence various changes in theconstruction and arrangement of the essential component parts may bemade without departing from the spirit and scope of the invention. As atypical example, the magnet component of the contactor device can be ofthe electrical type rather than the permanent type illustrated and itwill also be evident that the contactor device according to theinvention can be adapted to various other uses where a rotary type ofswitch is required.

I claim:

1. In an electrical contactor device, the combination comprising acontact disc of magnetic material mounted for displacement about acentral axis, contacting means disposed along a contacting circleconcentric with said axis adjacent the periphery of said disc, arotatable magnet having the pole portions thereof arranged for movementalong a circular path concentric with said axis adjacent the discsurface and circumferentially thereof, said disc being in a state ofcontinuous attraction to said magnet poles, and means for rotating saidmagnet whereby to effect displacement of a progressively changingportion of the disc surfacein the direction of said magnet poles and acorresponding progressive contact between the periphery of said disc andthe contacting means on said contacting circle.

2. An electrical contactor device as defined in claim 1 wherein saidmagnet is of the permanent type.

3. In an electrical contactor device, the combination comprising acontact disc of magnetic material, mounting means for said disc adaptingV the same for a wobble motion about the axis of the mounting means, aplurality of contacts arranged in spaced relation along a contact circlein the path of the periphery of said disc, a magnet having the polesthereof arranged for movement along a circular path concentric with saidcontact circle adjacent the surface of said disc, said disc surfacebeing in a state of continuous tilt by magnetic attraction to saidmagnet poles, and means for rotating said magnet thereby causing saiddisc to wobble on its mounting and to bring a progressively changingperipheral portion of said disc into successive engagement with saidcontacts.

4. An electrical contactor device as defined in claim 3 wherein saidmagnet is of the permanent type.

5. In an electrical contactor device, the combination comprising acontact disc of magnetic material, a ball and socket bearing for saiddisc located at the center thereof, a plurality of contacts arranged inspaced relation along a contact circle in the path of the periphery ofsaid disc, and means for imparting a wobble action to said disc on saidbearing to bring a progressively changing peripheral portion of saiddisc into successive engagement with said contacts comprising arotatable magnet having the poles thereof arranged for movement along acircular path concentric with said contact circle adjacent the surfaceof said disc, said disc surface being in a state of continuous tilt bymagnetic attraction to said magnet poles, and means for rotating saidmagnet.

6. In an electrical contactor device, the combination comprising acontact disc of magnetic adjacent the surface of said disc, said discsur-v face being in a state of continuous tilt by magnetic attraction tosaid magnet poles, and means for rotating said magnet.

7. An electrical contactor device as defined in claim 6 wherein saidcontacts upstand from the surface of said plate and the periphery ofsaid contact disc engages adjacent contacts on said contact circle whenthe low point on the periphery of said disc lies intermediate saidadjacent contacts.

8. An electric contact device as defined in claim 6 wherein said magnetis of the permanent type.

9. An electrical contactor device as defined in claim 6 wherein saidcontact disc includes a contact ring constituting the peripheral portionwhich engages said contacts.

10. An electrical contactor device as defined in claim 6 wherein themeans for rotating said magnet comprises a shaft arranged for rotationon an axis concentric with said bearing axis.

11. In an electrical contactor device, the combination comprising acontact disc of magnetic material, a support plate of insulatingmaterial, a ball and socket bearing for said disc carried by saidsupport plate, said disc being statically balanced on said bearing, aplurality of contacts arranged on said plate in spaced relation along acontact circle concentric with the axis of said bearing, a shaftarranged for rotation on an axis coincident with the axis of saidbearing, the end of said shaft including an/arcuate recess confrontingthe surface of the ball member of said bearing opposite the socketmember to prevent unseating of the same from the socket member, andmeans for imparting a wobble action to said disc on said bearing tobring a progressively changing peripheral portion of said disc intosuccessive engagement with said contacts comprising a magnet mounted onsaid shaft for rotation therewith, the poles of said magnet beingarranged to travel along a circular path concentric with said contactcircle adjacent the surface of said disc, said disc surface being in astate of continuous tilt by magnetic attraction to said magnet poles.

12. In an electrical contactor device the combination comprising acircular contact disc of magnetic material arranged for oscillatorymotion about a central axis in a plane transverse to such axis, aplurality of contacts arranged in spaced relation along a contact circleconcenric with said axis adjacent the periphery of said disc, the radiusof said contact circle being greater than that of said disc, a rotatablemagnet having the pole portions thereof arranged for movement in acircular path concentric with said axis adjacent the disc surface andcircumferentially thereof, the radius of the circular path of saidmagnet poles being greater than that of said disc, and the periphery ofsaid disc being in a state of continuous radially outward attraction tosaid magnet poles eccentrically of said axis, and means for rotatingsaid magnet thereby to cause a progressively changing radially displacedperipheral portion of said disc to engage the contacts on said contactcircle in succession.

13. An electrical contactor device as defined in claim 12 and whichfurther includes a guide plate for said contact disc arranged in spacedparallel relation to said contact disc and roller means between saidguide plate and contact disc.

14. An electrical contactor device as defined in claim 13 wherein saidmagnet, and guide plate are carried by a rotatable cylindrical shaftarranged coaxially with said central axis and which passes through acentral circular aperture in said contact disc having a diameter greaterthan 10 that of said shaft by an amount equal to the radial displacementof said disc.

15. An electrical contactor device as defined in claim 12 wherein theunlike pole portions of said magnet present arcuate faces arranged inmutually confronting relation at the periphery of said contact disc andthe gap between said pole faces extends perpendicular to the plane ofthe disc.

16. An electrical contactor device as defined in claim 12 wherein theunlike pole portions of said magnet are arranged to establish a gaptherebetween extending parallel to the plane of the disc.

PETER VAN SANTEN KOLFF.

No references cited.

